Congenital Anomalies of the Kidneys, Collecting System, Bladder, and

Halima S. Janjua, MD,* Suet Kam Lam, MD, MPH, MS,† Vedant Gupta, DO,‡ Sangeeta Krishna, MD† *Center for Pediatric Nephrology, †Department of Pediatric Hospital Medicine, ‡Department of Pediatrics, Cleveland Clinic Children’s, Cleveland, OH

Education Gap

Several congenital anomalies of the kidney and urinary tract are incidental findings. An understanding of when to suspect and how to diagnose, manage, and use timely and appropriate investigations and consults is necessary.

Objectives After completing this article, readers should be able to:

1. Develop an awareness of various congenital anomalies of the renal system, including embryology, prevalence, and risk factors. 2. Describe the clinical presentation and management of renal and urinary tract anomalies, including which anomalies warrant further evaluation and the timing and utility of imaging modalities. 3. Develop an awareness of genetic syndromes affecting the kidneys and urinary tract with associated extrarenal manifestations.

INTRODUCTION

Congenital anomalies of the kidney and urinary tract (CAKUT) include a wide spectrum of anomalies, with a reported incidence of up to 2% of births. (1) CAKUT account for almost one-fourth of all birth defects. (2) These are major AUTHOR DISCLOSURE Drs Janjua, Lam, Gupta, and Krishna have disclosed no causes of in children and account for more than 40% of end-stage financial relationships relevant to this article. renal disease (ESRD). CAKUT are usually detected by routine prenatal ultraso- This commentary does not contain a nography, although some cases are not diagnosed until adulthood. (3) discussion of an unapproved/investigative When renal disease is suspected, a complete physical examination should be use of a commercial product/device. performed with particular focus on accurate blood pressure measurement; the abdomen ABBREVIATIONS for palpable kidneys and a distended bladder; the genitalia for the position of the meatus, ARPKD autosomal recessive polycystic penile abnormalities, and urine flow; and the back for signs of neural tube defects. kidney disease Genetics play a major role in the etiology of CAKUT as family history is CAKUT congenital anomalies of the kidney identified in 10% to 50% of affected children (Table). (4)(5) Similarly, 23% of asymp- and urinary tract fi ESRD end-stage renal disease tomatic rst-degree relatives are found to be affected on screening. (4) Many MCDK multicystic dysplastic kidney environmental factors, such as maternal medication exposure, folate and iron PUV deficiency, and diabetes mellitus, also contribute to the expression of CAKUT. RBUS renal and bladder ultrasonography UPJ ureteropelvic junction UTI PATHOGENESIS UVJ ureterovesical junction VCUG voiding cystourethrogram Human kidneys develop in 3 stages: the pronephros, the mesonephros, and the VUR vesicoureteral reflux metanephros. The pronephros and the mesonephros involute, and the metanephros

Vol. 40 No. 12 DECEMBER 2019 619 forms the kidney starting at the fifth week of embryogenesis. The with urinary tract anomalies, such as , kidneys lie in the initially, where they are adjacent to each ureteral duplication, hydroureter, ureteropelvic junction other and facing ventrally. By the eighth week of embryogenesis, (UPJ) and ureterovesical junction (UVJ) obstruction, and the kidneys migrate to their permanent location in the lumbar vesicoureteral reflux (VUR). (13) Although renal and bladder region, and by the tenth week, they start producing urine. At the ultrasonography (RBUS) can capture a small hyperechoic time of birth, each healthy kidney measures approximately 4.0 kidney, histologic analysis can show undifferentiated tissue, to4.5cminthelongestdimension.Withtheco-expressionof nephron cell structure, and the presence of cartilage and multiple signaling and transcription factors, there are reciprocal cysts. Unilateral dysplasia has a good prognosis, barring the interactions between the metanephros and ureteric epithelium, severity of comorbidities of concomitant anomalies. How- resulting in the formation of nephrons and the collecting system. ever, unilateral renal dysplasia also may lead to death due to In the meantime, the bladder develops from the urogenital the or chronic kidney disease. sinus. Malfunctioning of otherwise well-controlled signaling pathways and transcription factors can result in CAKUT. (6) Multicystic Dysplastic Kidney The most common cause of a congenital solitary kidney is unilateral multicystic dysplastic kidney (MCDK). The prevalence ANOMALIES OF THE KIDNEY of MCDK is 1 in 2,400 to 1 in 4,300 live births, and it disproportionately affects males and the left side. (14) Most MCDKs involute without intervention (60% by age 10 years) Renal agenesis or aplasia is a missing kidney, with the and have minimal functional nephrons or renal tissue. (15) Most former a result of embryologic lack of initiation of devel- cases of MCDK are detected prenatally via ultrasonography, and opment and the latter of failure to progress after initial they are the second most common cause of newborn abdominal induction and subsequent involution. The incidence of masses, with being the first. There are many unilateral renal agenesis is 1 in 1,000 to 1 in 3,000 live isolated cysts of differing sizes with dysplastic stroma associated births, with males and the left side disproportionately with an atretic on gross examination. The contralateral affected. (7)(8) Diagnosis is usually made on routine pre- kidney may be affected by low-grade VUR in 15% to 28% of natal ultrasonography without obvious physical examina- patients or by UPJ obstruction in 4% of patients. (15)(16) Serial tion signs or symptoms, although there is a 50% rate of postnatal RBUS is warranted to monitor for contralateral renal coexisting urogenital abnormalities. During fetal develop- abnormalities, growth, and involution. If involution occurs, ment, the contralateral kidney undergoes hypertrophy as a further RBUS is not necessary. Malignant transformation compensatory response to the effects of a decreased neph- (Wilms tumor or renal cell carcinoma) is rare; therefore, ron count. The single hypertrophied kidney hyperfiltrates nephrectomy of MCDK is no longer the treatment of choice. and develops renal injury marked by hypertension, pro- (14) Conservative management with regular screening for hyper- teinuria, and reduced glomerular filtration rate. (9) Hence, tension and proteinuria is needed in patients with MCDK. serial ultrasonography and routine screening for hyperten- sion and proteinuria into adulthood are warranted. In a Autosomal Recessive Polycystic Kidney Disease study, the median age at renal injury was 14.8 years in a Autosomal recessive polycystic kidney disease (ARPKD) is cohort of 151 pediatric patients with a solitary functioning an inheritable genetic disorder with an incidence of 1 in kidney. (10) Bilateral agenesis has a male predominance and 10,000 to 1 in 40,000 live births. (17) Although ARPKD can is rare, occurring in 1 in 7,000 to 1 in 10,000 births. (11) present later in life, it is typically thought of as an “infantile” Those affected generally do not survive after birth because disease. Prenatal ultrasonography shows bilateral en- oligohydramnios leads to the Potter sequence, with multiple larged hyperechoic kidneys and possibly oligohydramnios. anomalies of the lung, limb, and face. Although 30% of newborns with ARPKD die after birth, postinfancy survival is 80% at 10 years. (17) Most infants Renal Dysplasia develop difficult to control hypertension, and 20% to 45% A dysplastic kidney occurs due to abnormal differentiation have ESRD by age 15 years. (18) On examination at birth, after initiation of normal development and is one of the most patients have bilateral firm abdominal masses and possibly common causes of pediatric ESRD. Prevalence ranges from respiratory distress. Laboratory work will show increasing 0.1% on ultrasonography screening to 4% in infant autopsies. blood urea nitrogen and serum creatinine levels, indicative (12) Unilateral dysplasia is more common than bilateral of renal insufficiency. The bilateral renal cystic disease and dysplasia, and as many as 50% to 75% of cases are associated associated hepatic fibrosis lead to renal and hepatic

620 Pediatrics in Review insufficiency. Although renal impairment can be variable, on the lower abdomen for a distended bladder, genitalia for all patients have hepatic fibrosis. penile abnormalities and urine flow, and the back for signs of Diagnosis is made by imaging and the infant having at neural tube defects, which may be associated with a neurogenic least 1 of the following: both parents without renal cysts, a bladder. (21) Blood work assessing kidney function is generally sibling with ARPKD, consanguineous parents, or hepatic withheld, except in bilateral hydronephrosis and severe cases. fibrosis. Management of the infant may include respiratory RBUS is useful in determining the severity of hydro- support, hypertension control, or fluid and electrolyte sup- nephrosis, for which multiple classification systems exist. port. Nephrectomy may be an option if the enlargement is The urinary tract dilation classification system is widely severe enough to affect respiratory or digestive function. As used, which includes parameters on anteroposterior renal the patient grows older, dialysis for advanced kidney disease pelvic diameter, calyceal dilation, parenchymal thickness or surgery for portal hypertension may be required. and appearance, and ureter and bladder abnormality. (20) The Society for Fetal Urology classifies diseases on the Autosomal Dominant Polycystic Kidney Disease anteroposterior renal pelvic diameter and on the appearance Autosomal dominant polycystic kidney disease is the most of the kidney, ureter, and bladder. (22) Postnatally in a low- common inheritable genetic renal cystic disease, with an risk patient with unilateral hydronephrosis, RBUS can be incidence of 1 to 2 in 1,000 live births. (17) Genetic testing is performed 7 to 10 days after birth. (20)(23) Exceptions to usually reserved for unclear diagnosis or if a family member delayed imaging include cases of oligohydramnios, urethral is being considered for kidney donation for transplant. obstruction, bilateral high-grade dilation, and follow-up Although this disease generally presents later in life (30–40 concerns. (23) In bilateral hydronephrosis or a high-risk years of age), it can present in infancy with a poor prognosis. infant with bladder dilation, delivery at a center with pedi- Clinical presentations may range from abdominal masses in the atric urology support is recommended. A high-risk maternal/ newborn to abdominal or flank pain between the third and fifth fetal medicine specialist should be involved when there are decades of life. Hematuria, hypertension, or gastrointestinal findings of oligohydramnios. If the lower urinary tract symptoms may be seen in adults. Hypertension occurs in half is involved and there is bladder distention and/or bilat- of the patients by their third decade of life and in almost all eral hydroureteronephrosis, voiding cystourethrography patients with ESRD. Other complications include hematuria, (VCUG) should be performed to rule out PUVs, and initi- urinary tract infection (UTI), cerebral aneurysm, or heart disease, ation of antibiotic prophylaxis is recommended. (20) with mitral valve prolapse as the most common valvular disorder. (17) Extrarenal manifestations occur most commonly in the liver, Vesicoureteral Reflux followed by cysts in the seminal vesicles, arachnoid membrane, VUR is the most common pediatric urologic condition, affect- and pancreas. (19) In contrast to ARPKD, macroscopic cysts are ing up to 30% of children with a febrile UTI and 0.4% to 1.8% seen on ultrasonography. Asymptomatic children with affected of the general pediatric population. (24) In infants with pre- parents should be screened annually with blood pressure mea- natal hydronephrosis, 10% to 20% will have VUR. It is seen in surements and urinalysis. Management includes supportive care 50% of children of parents with VUR and 25% of siblings with for respiratory or renal issues in infancy and long-term medical VUR. (25) Primary reflux is an embryonic anatomical defect management of renal insufficiency and hypertension. Patients and largely spontaneously self-resolves with elongation of the presenting with flank or abdominal pain and/or fever should be intravesical tunnel at the UVJ as the child grows. Secondary evaluated for infection, urinary stones, or tumors. Nephrectomy VUR occurs when increased intravesical pressures lead to may be performed in selective symptomatic patients. retrograde urine flow past the normal UVJ. This can be due to disorders such as neurogenic bladder, PUVs, or bowel and ANOMALIES OF THE COLLECTING SYSTEM bladder dysfunction in anatomically normal children. Correc- tion of bowel and bladder dysfunction may resolve VUR. (26) Hydronephrosis Management of VUR is controversial and may include Hydronephrosis is the dilation of the renal pelvis and calyces antibiotic prophylaxis and/or surgical correction, taking into secondary to increased urine retention. In 50% to 75% of consideration patient age, severity, renal scarring, and paren- the cases, hydronephrosis is transient or physiologic. Other tal preference. A meta-analysis that included the RIVUR causes, such as UPJ obstruction and VUR, have an incidence of (Randomized Intervention for Children with Vesicoureteral 10% to 30%. Less common causes include UVJ obstruction, Reflux) and PRIVENT (Prevention of Recurrent Urinary Tract MCDK, or posterior urethral valves (PUVs). (20) A complete Infection in Children with Vesicoureteric Reflux and Normal physical examination should be performed with particular focus Renal Tracts) studies demonstrated that although antibiotic

Vol. 40 No. 12 DECEMBER 2019 621 prophylaxis can reduce UTIs, it does not reduce kidney bladder dysfunction and nearly all cases of myelomeningocele scarring.(27)Furthermore,antibiotic-resistantbacteria are associated with a neurogenic bladder. (36)(37) The initial increasingly cause infections while the patient is on pro- evaluation should include a neurologic examination. Check- phylaxis. Complications of VUR include pyelonephritis, renal ing muscle mass, tone, spontaneous movements, deep tendon scarring, hypertension, and chronic kidney disease. reflexes, and skinfolds can help determine neurologic func- tion and localize the dysraphism level. Of note, the level of Duplicated Collecting System dysraphism is poorly predictive of bladder dysfunction, and a Duplications of the collecting system are the result of abnor- separate complete bladder evaluation is recommended. (38) mal embryonic origins. Complete duplication is a double Secondary VUR occurs when increased intravesical pres- ureter, each draining separately into the bladder, whereas sures lead to retrograde urine flow past the normal UVJ. partial duplication presents with a bifid ureter with a single This can be due to disorders such as a neurogenic bladder, drain into the bladder. (28) VUR is usually present in the PUVs, or bowel and bladder dysfunction in anatomically lower moiety of a duplicated collecting system, whereas the normal children. Correction of bowel and bladder dysfunc- upper moiety is associated with an obstructive , tion may resolve VUR. (31)(38) Early determination of with or without a ureterocele. The prevalence of ureteral bladder function allows for more proactive treatment and duplications is less than 1% of the general population and will guide future surveillance and management. (31)(38)(39) affectsfemales2to4timesmoreoftenthanmales.(29) No intervention is necessary if complete bladder empty- Complications of a duplicated collecting system include VUR, ing is noted, regardless of the degree of bladder denervation. obstruction, ectopic ureteral insertion, and ureteroceles. (28) Any sign of bladder dyssynergy, incontinence, incomplete Ultrasonography is the mainstay of diagnosis, both before and emptying, or urinary tract abnormalities warrants further after birth, and is the most common modality for incidental intervention. Treatment is guided by the initial assessment findings of duplication. (30) VCUG can help determine VUR and may include anticholinergic medications and intermit- and voiding patterns. Management differs widely, based on tent or continuous catheterization. If symptoms worsen anatomical abnormality, function, and VUR severity. despite initial treatment, then surgical intervention is indi- cated. (39)(40)(41)(42) Failure to intervene early can lead to ANOMALIES OF THE BLADDER high-grade VUR and recurrent UTIs, leading to irreversible renal injury. Patients with congenital neurogenic bladder will Congenital Neurogenic Bladder need regular surveillance visits and imaging to monitor the Bladder dysfunction results from disruptions of the normal urinary tract and bladder function. (38)(41) Patients born with voiding process by neurogenic, anatomical, or functional spinal dysraphism can have secondary spinal cord injury over causes. (31) The most frequent neurogenic cause is spinal time associated with growth and fibrosis. (43) Prognosis for dysraphism, a spectrum of congenital abnormalities that in- these patients has dramatically improved in the past 3 decades cludes open and closed forms. Folic acid deficiency is the major due to advancements in detection, minimally invasive ther- etiology for these disorders and leads to the failure of complete apies, and higher levels of urologic care. (38) closure of the spinal neural tube. (32) Other less common risk factors include chromosomal abnormalities and gene muta- ANOMALIES OF THE URETHRA tions. (33) The estimated incidence of spinal dysraphism is approximately 0.1%. (34) However, the incidence has been Posterior Urethral Valves declining worldwide during the past few decades due to better PUVs are characterized by abnormal mucosal folds at the nutrition and supplementation for pregnant mothers and prostatic urethra level that function as a valve to obstruct urine improved prenatal care. (35) Other neurogenic etiologies include flow. (44) They are the most common cause of congenital sacral agenesis, cerebral palsy, and traumatic spinal cord injuries. urethral obstruction, affecting 1 in 5,000 to 1 in 25,000 live Myelomeningocele is the most common and severe form male births. (45)(46) Prenatal ultrasonography may show of neural tube defects and accounts for 85% of all open spinal bilateral hydronephrosis, a thick-walled bladder, dilated dysraphisms. (36) A myelomeningocele involves an opening posterior urethra, and/or oligohydramnios. (45) If not diag- in the spine where both nerve roots and spinal cord tissue nosed prenatally, PUVs can present in newborns with intra- protrude into a fluid-filled sac on the back. (34) Due to incom- uterine growth retardation and a weak voiding stream. Older plete closure of the vertebral column and the risk of exposed children can present with recurrent UTIs, urosepsis, renal spinal canal contents, urgent evaluation and treatment are failure, or incontinence. VCUG remains the gold standard needed. As many as 60% of all cases have some form of for detecting PUV and will show the proximal urethra more

622 Pediatrics in Review dilated than the urethra distal to the valve. A urethral catheter and wrinkled overlying skin and bilateral cryptorchidism. RBUS should be placed in the bladder to relieve the obstruction. (46) reveals dilation of the urinary tract secondary to urethral The treatment of choice is transurethral valve ablation, with obstruction. (52) Nearly 50% of patients have associated car- diversion of the obstructed bladder via vesicostomy as an diovascular, gastrointestinal, or orthopedic malformations, and alternative. (47) PUVs continue to have high mortality and all patients have some degree of renal dysplasia. (53) These morbidity (48) and are the most common cause of obstructive patients have a high incidence of chronic kidney disease, with uropathy leading to ESRD. (49)(50) 40% to 50% of patients needing renal replacement therapy. (54) Eagle-Barrett syndrome, also known as prune belly syn- drome, is a rare lower urinary tract malformation affecting 1 Urethral Stricture in 30,000 newborns, with 95% of patients being males. (51) Congenital urethral strictures are a rare urethral anomaly. Prenatal ultrasonography reveals findings similar to PUVs. These patients can be identified prenatally with abdominal Diagnosis at birth is established clinically with pathognomonic imaging findings similar to PUV. (55) After birth, patients findings of deficiency of abdominal wall musculature with loose present with obstructive and irritative symptoms, such as

TABLE. Genetic Syndromes Associated with CAKUT

SYNDROME RENAL ABNORMALITY EXTRARENAL MANIFESTATIONS

Turner Renal agenesis, hypoplasia Short stature, amenorrhea, webbed neck, cubitus valgus, hypogonadism Down Renal agenesis Intellectual disability, hypotonia, congenital heart disease, clinodactyly Patau Renal agenesis Holoprosencephaly, midline anomalies, cleft lip/palate CHARGE Many urinary tract malformations Cardiac defects, cleft palate, hearing loss, coloboma, choanal atresia, genital anomalies Di George Renal agenesis, dysplasia, VUR Cardiac defects, cleft palate, thymic aplasia, hypocalcemia, immunodeficiency Renal coloboma Renal hypoplasia, MCDK, VUR Optic disc/nerve anomalies, hearing loss, CNS and genital anomalies, skin and ligamentous laxity Orofaciodigital Renal cysts Lobed tongue, cleft palate, hypodontia, micrognathia clinodactyly Branchio-oto-renal Renal agenesis, dysplasia Lateral cervical fistulas or cysts, ear pits, hearing loss Renal cysts and Renal dysplasia, cysts Diabetes mellitus diabetes Fraser Renal agenesis, dysplasia Cryptophthalmos, syndactyly, tracheal stenosis/atresia, ambiguous genitalia, craniofacial anomalies Alagille MCDK, renal dysplasia, mesangiolipidosis Chronic cholestasis, cirrhosis, cardiac anomalies, butterfly vertebrae, dysmorphic facies Bardet-Biedl Renal dysplasia, calyceal malformations Obesity, intellectual disability, retinal dystrophy, polydactyly Beckwith-Wiedemann Nephromegaly, nephrocalcinosis, medullary sponge Macrosomia, hemihyperplasia, macroglossia, kidney Simpson-Golabi- Variety of kidney and urinary tract malformations Craniofacial anomalies, organomegaly, tumors, intellectual Behmel deficiency Smith-Lemli-Opitz Renal hypoplasia Syndactyly, microcephaly, intellectual disability, heart, lung, and gastrointestinal abnormalities Rubinstein-Taybi Variety of kidney malformations Highly arched eyebrows, high-arched palate, micrognathia, internally deviated toes and thumbs, hirsutism, heart and eye abnormalities

Abbreviations: CAKUT¼congenital anomalies of the kidney and urinary tract, CNS¼central nervous system, MCDK¼multicystic dysplastic kidney, VUR¼vesicoureteral reflux.

Vol. 40 No. 12 DECEMBER 2019 623 urinary retention, dysuria, or weak stream. Diagnosis is made with VCUG, and treatment is with urethral dilatation, endo- Summary scopic repair, or vesicostomy if severe. Acquired urethral • Based on strong research evidence, hydronephrosis is the most strictures are usually due to urethral instrumentation but common cause of abnormal prenatal ultrasonography and can have inflammatory and traumatic etiologies as well. (56) abdominal masses in newborns. The urinary tract dilation classification system and the Society for Fetal Urology classification system are widely used for disease severity fi Hypospadiasisthemost common malformation of the male classi cation and management. (20)(22) • fl genitalia, with an incidence of 0.3% to 0.5% in live male births. Based on strong research evidence, vesicoureteral re ux is the most common pediatric urologic condition, affecting up to 30% (57) It results in abnormal ventral placement of the urethral of children with a febrile urinary tract infection and 0.4% to 1.8% opening anywhere along the penis, scrotum, or perineum. of the general pediatric population. (24) Management remains a Hypospadias is a clinical diagnosis and is usually made during controversial topic and is the subject of ongoing research. the newborn examination. Hypospadias can present in older • Based on consensus, ultrasonography is the imaging of choice for children and teens with a weak, downward-angled stream and, initial evaluation prenatally and after birth to evaluate congenital when associated with chordee, painful sexual intercourse. (58) anomalies of the kidney and urinary tract and is the image of The examination should focus on identifying other associated choice for the initial evaluation of various diagnoses, to classify severity of disease, and to guide future monitoring. anomalies, the exact anatomical location of the meatus, assess- • ment of the foreskin, and the presence of chordee. Newborn Based on strong research evidence, posterior urethral valves are most commonly diagnosed prenatally with ultrasonography circumcision is contraindicated because the foreskin may be findings of bilateral hydronephrosis, dilated posterior urethra, used for urethral and penile reconstruction. Surgical repair is and/or oligohydramnios. (45) Based on some research evidence elective and is ideally performed at 6 to 12 months of age. (59) as well as consensus, the treatment of choice is transurethral valve ablation. (47) • Based on strong research evidence, hypospadias is the most Epispadias is a congenital malformation of the urethra that common malformation of the male genitalia. Newborn can present as an isolated finding or can be associated with circumcision is contraindicated in these patients, and surgical repair is ideally performed at 6 to 12 months of age. (60) bladder exstrophy, a condition referred to as the exstrophy- epispadias complex. Epispadias is found in nearly all cases of bladder exstrophy and has an incidence of 1 in 30,000 live SUGGESTED QUALITY IMPROVEMENT PROJECT births, with a male preponderance. (60) Epispadias presents as a partial or complete opening of the urethral meatus on the • Improve the tracking of the multidisciplinary follow-up of dorsal surface. In males, the urethral meatus can be located the patient with urinary abnormalities. anywhere from the distal penile shaft to the pubic area. (61) In females, epispadias is associated with a bifidclitorisand anteriorly displaced vaginal orifice. (62) Isolated epispadias To view teaching slides that accompany this article, is much less common, with an incidence of 0.5 in 100,000 visit http://pedsinreview.aappublications.org/ live births in males and an even lower incidence in females. content/40/12/619.supplemental. (61) Epispadias is usually evident on examination at birth and is strongly associated with . RBUS should be performed to assess the urinary tract. (62) Surgical repair should be pursued as early as possible for both sexes. To maintain bladder function and continence, these patients may need multiple surgeries throughout their lifetime. (62)

GENETIC SYNDROMES ASSOCIATED WITH CAKUT

There is increasing evidence of genetic abnormalities as the cause of CAKUT. Identifying the underlying genetic involvement may improve identification and management of extrarenal manifestations. There are more than 500 genetic References for this article are at http://pedsinreview.aappub- syndromes with renal or urinary tract abnormalities. (5) lications.org/content/40/12/619.

624 Pediatrics in Review PIR Quiz Individual CME quizzes are available via the blue CME link under the article title in the Table of Contents of any issue. To learn how to claim MOC points, go to: http://www.aappublications.org/content/moc-credit.

REQUIREMENTS: Learners 1. You are seeing a 2-week-old female newborn for her first physical examination after can take Pediatrics in Review discharge from the nursery. She was diagnosed prenatally with a solitary left kidney by quizzes and claim credit prenatal ultrasonography. You decide to order repeated renal ultrasonography today. online only at: http:// In explaining your reasoning to the parents, which of the following statements best pedsinreview.org. describes your rationale for ordering the ultrasonography today? To successfully complete A. Only 10% of affected children have a problem in the solitary kidney, and this is 2019 Pediatrics in Review just a precaution to make everyone feel better. articles for AMA PRA B. Renal agenesis is associated with liver cysts 30% of the time, so you need the Category 1 CreditTM, learners ultrasonography to look at the liver also. must demonstrate a minimum C. The solitary kidney is often affected by nephrocalcinosis and ultrasonography is performance level of 60% or needed to assess the extent of calcium deposits. higher on this assessment. D. The solitary kidney is typically smaller than normal because of a lack of growth factors If you score less than 60% from the other kidney, and follow-up ultrasonography is needed to check its growth on the assessment, you rate. will be given additional E. Up to 50% of children with 1 kidney can have a problem in the contralateral opportunities to answer urogenital tract. questions until an overall 60% or greater score is achieved. 2. You are called to the newborn nursery because the nursing staff noted abdominal fullness This journal-based CME on the right side of the abdomen while bathing a full-term male newborn infant. The baby is activity is available through urinating normally, and there is no gross hematuria. On physical examination the baby is Dec. 31, 2021, however, credit afebrile. His pulse is 120 beats/min, blood pressure is 100/60 mm Hg, and respiratory rate will be recorded in the year in is 50 breaths/min. On physical examination you are able to palpate a large mass on the which the learner completes right side of the abdomen, and it does not cross the midline. The lungs are clear, but the quiz. breath sounds are decreased on the right side. Which of the following is the most likely diagnosis in this patient? A. Hydronephrosis. B. Multicystic dysplastic kidney. C. Neuroblastoma. D. Renal cell carcinoma. 2019 Pediatrics in Review now E. Wilms tumor. is approved for a total of 30 Maintenance of Certification 3. You are examining a 48-hour-old full-term male newborn in the nursery. The mother is only (MOC) Part 2 credits by the 16 years of age and did not have prenatal care because she was trying to hide the pregnancy American Board of Pediatrics from her parents and took no medications or supplements and had no prenatal through the AAP MOC ultrasonography. She occasionally smoked cigarettes and marijuana but stopped late in her Portfolio Program. Complete first trimester when she learned she was pregnant. She used condoms inconsistently. Her the first 10 issues or a total of medical history is significant for sexually transmitted infections, including gonorrhea and 30 quizzes of journal CME chlamydia, 6 months before her pregnancy. The baby is making approximately 6 wet credits, achieve a 60% passing diapers a day without any hematuria. On physical examination you note the presence of a score on each, and start deep sacral pit and you are unable to visualize its bottom. The muscle tone in the lower claiming MOC credits as early extremities is noticeably decreased. An evaluation is started. Which of the following factors as October 2019. To learn how most likely placed this infant at the greatest risk for possibly having this condition? to claim MOC points, go to: A. Being first born. http://www.aappublications. B. History of marijuana and tobacco use. org/content/moc-credit. C. History of sexually transmitted infections. D. Lack of intake of prenatal vitamins. E. Maternal age.

Vol. 40 No. 12 DECEMBER 2019 625 4. A 15-month-old boy is brought to the clinic for follow-up. He is new to the practice because the family just moved to the area. The baby was not previously seen by a primary care clinician and received no immunizations so far due to the family being uninsured. The father just started a new job in the area that provided him with insurance. Physical examination is significant for macrosomia, hemihyperplasia, and macroglossia. Further testing of the kidneys and urinary tract system is warranted because these clinical findings may be associated with which of the following conditions? A. Epispadias. B. . C. Neurogenic bladder. D. Renal agenesis. E. Renal cysts.

5. A 5-year-old boy is brought to the emergency department with a temperature of 102.2°F (39°C) and emesis for the past 24 hours. He was born at full-term and has never been diagnosed as having any medical problems. He is up-to-date on his vaccines. Physical examination reveals an ill-looking child with a pulse of 100 beats/min, blood pressure of 70/ 50 mm Hg, and a respiratory rate of 30 breaths/min. He has diffuse abdominal tenderness. His white blood cell count is 18,000/mL (18109/L). Urinalysis shows nitrates and leukocytes. Blood and urine cultures are pending. A fluid bolus is given, and he is started on intravenous antibiotics and admitted to the hospital for hydration. Which of the following imaging studies is the most appropriate next step in assessing the cause of his symptoms? A. Abdominal radiography. B. Computed tomography of the abdomen. C. Intravenous pyelography. D. Renal ultrasonography. E. Voiding cystourethrography.

626 Pediatrics in Review Congenital Anomalies of the Kidneys, Collecting System, Bladder, and Urethra Halima S. Janjua, Suet Kam Lam, Vedant Gupta and Sangeeta Krishna Pediatrics in Review 2019;40;619 DOI: 10.1542/pir.2018-0242

Updated Information & including high resolution figures, can be found at: Services http://pedsinreview.aappublications.org/content/40/12/619 Supplementary Material Supplementary material can be found at: http://pedsinreview.aappublications.org/content/suppl/2019/11/27/40 .12.619.DC1 References This article cites 57 articles, 5 of which you can access for free at: http://pedsinreview.aappublications.org/content/40/12/619.full#ref-li st-1 Subspecialty Collections This article, along with others on similar topics, appears in the following collection(s): Nephrology http://classic.pedsinreview.aappublications.org/cgi/collection/nephro logy_sub Urology http://classic.pedsinreview.aappublications.org/cgi/collection/urolog y_sub Genitourinary Disorders http://classic.pedsinreview.aappublications.org/cgi/collection/genitou rinary_disorders_sub Permissions & Licensing Information about reproducing this article in parts (figures, tables) or in its entirety can be found online at: https://shop.aap.org/licensing-permissions/ Reprints Information about ordering reprints can be found online: http://classic.pedsinreview.aappublications.org/content/reprints Congenital Anomalies of the Kidneys, Collecting System, Bladder, and Urethra Halima S. Janjua, Suet Kam Lam, Vedant Gupta and Sangeeta Krishna Pediatrics in Review 2019;40;619 DOI: 10.1542/pir.2018-0242

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